-----Original Message-----
From: Carl S. Gutekunst [mailto:csg(_at_)alameth(_dot_)org]
Sent: Friday, October 28, 2011 11:51 PM
To: Murray S. Kucherawy
Cc: ietf-smtp(_at_)imc(_dot_)org
Subject: Re: 4yz Temporary Rejections is part of the SMTP Protocol
Before we try anything like that, we need actual feature negotiation
(not just announcements), which ESMTP lacks.
The closest thing is ENHANCEDSTATUSCODES, which doesn't seem to have been much
of a problem so far. That's probably the most palatable path.